Kenichi Amamiya's eyes held a thoughtful look. He was currently researching a new ninjutsu, one he had created based on some of his discoveries from this period. The ninjutsu itself even contained many tedious and complex elements. Kenichi Amamiya's gaze carried a hint of hesitation. He glanced at Orochimaru beside him and scratched his head. He had originally planned to ask his teacher what he thought about these things, but what Kenichi Amamiya had not expected was that Orochimaru did not immediately answer his question. Instead, he pulled out a new ninjutsu. Orochimaru said it was a ninjutsu he had conceived during this period. Hearing that, Kenichi Amamiya was somewhat surprised. Ever since Orochimaru had begun studying science, Kenichi Amamiya could tell that his teacher no longer had much interest in this area. At the very least, there were many things he had neither researched nor understood. With that in mind, Kenichi Amamiya curiously looked over what his teacher had developed. After examining it, he was astonished to discover that the ninjutsu Orochimaru had developed was indeed very interesting. It was a different kind of brain-transplant technique, directly replacing a human brain to achieve a new form of immortality. It was extremely fast, had virtually no side effects, and could even achieve an almost one-hundred-percent compatibility rate. That was truly remarkable. Kenichi Amamiya narrowed his eyes, deep in thought. If this had been placed in his previous life, it would probably have attracted the attention of many people. After all, it was another form of immortality, and once civilization developed to a certain stage, people naturally began pursuing it anew.
However, this did not hold much significance in the Shinobi World. To some extent, the current Shinobi World had already achieved new methods of immortality. The simplest was life extension,